[2F09-13] Environmental Dynamics

[2F10] Numerical simulation of radiocesium dynamics during flooding events in rivers in Fukushima

*Keisuke Taniguchi¹, Kouki Nasu², Hirotsugu Arai², Yukio Takeuchi², Kazumi Katsuno², Kazuki Fujita², Yasuo Onishi³ (1. NIT Tsuyama College, 2. FPCEC, 3. Higashi Nippon International Univ.)

Keywords:Radiocaesium, River, Fukushima Daiichi nuclear power plant accident

The accident at the Fukushima Daiichi Nuclear Power Plant in March 2011 caused the release of Cs-137 into the surrounding area. While the decontamination works have been carried out in the residential areas and farmlands for eleven years after the accident, the practices have not yet been conducted in the headwater forest areas. This study used a one-dimensional finite element code, TODAM, to simulate the dynamics of Cs-137 in a river with a high initial deposition in a part of the river basin. By setting the parameters based on the particle size distribution data of actual samples, we could reproduce the change in Cs-137 concentrations in the river waters during flooding events.